The trucking industry “keeps America moving” and trucking is in fact one of the most important modes of transportation for the movement of goods. Trucks are able to make long hauls or short hauls and can deliver to almost any location accessible by a paved road. Trucking, however, is a dangerous industry for reasons tied to this versatility. Trucks share the nation's roadways with passenger vehicles and pedestrians. Because the size of trucks almost always exceeds other vehicles, truck drivers must be especially careful to observe smaller vehicles and prevent collisions therewith. This is especially true in the case of tractor trailer combinations which exceed a common passenger vehicle's size. The inherent design for the towed trailer is long in length, narrow in width, and commonly uses its capacity to carry heavy loads at a high center of gravity.
Tractor trailer combinations are vulnerable to the phenomenon known as rollover which occurs typically when a truck driver attempts to avoid a collision, or obstacle through a knee jerk impulse reaction. Additionally, rollovers prevalently occur at lane changes and ramp interchanges where excessive speed is used with a change of direction maneuver. The momentum of the trailer does not allow the trailer to follow the new path dictated by the tractor. Instead, the trailer tries to continue in its original path and begins to roll over from an upright position. This is a progressive event which starts at the rear of the trailer and rapidly progresses forward to involve the towing tractor; first its drive axle and continues to involve the forward steer axle which will then have committed the whole combination. The tractor, which is linked to the trailer via a kingpin and fifth wheel system, is actually pulled over by the dominant rolling trailer. Known kingpins include a shank having a circular diameter and an integral head portion also with a circular cross section, but with a larger diameter than the shank. Combination vehicle rollovers destroy the towing tractor, are known to have caused the death of hundreds of tractor occupants and cause vast amounts of serious injuries. Thousands of these events occur annually.
What is desired is a system that allows a towed trailer, within a tractor trailer combination vehicle, to mechanically detach itself from the towing tractor's fifth wheel receiver when the imminent rollover event has committed the towed trailer to roll onto its side, but allows the tractor to remain upright and not follow through to destruction in these events.